In afternoon trade S&P/ASX 200 Index (ASX: XJO) is on course to record a strong gain. At the time of writing, the benchmark index is up 0.8% to 8,004.2 points.

Four ASX shares that are rising more than most today are listed below. Here's why they are climbing:

Clinuvel Pharmaceuticals Limited (ASX: CUV)

The Clinuvel Pharmaceuticals share price is up over 2% to $11.98. This follows the release of promising preliminary results from its second clinical study investigating its drug afamelanotide as a treatment for arterial ischaemic stroke (AIS). Clinuvel's Chair, Prof Jeffrey Rosenfeld, said: "While considerable progress has been made in treating stroke with approved therapies, a large number of patients remain ineligible for existing therapies. Afamelanotide represents an innovative approach, taking a drug with a long-standing safety profile and evaluating whether a known mechanism of action may provide a therapeutic option for these previously untreated patients."

Orthocell Ltd (ASX: OCC)

The Orthocell share price is up 2.5% to $1.54. Investors have been buying the regenerative medicine company's shares after it announced the first sales of Striate+ in Germany, Austria and Switzerland. Striate+ is the company's dental guided bone and tissue regeneration product. The global market opportunity for Striate+ is estimated to be approximately >US$730 million, with the EU and UK market contributing approximately US$180 million. Orthocell is targeting a 20% share of the global market.

Vulcan Energy Resources Ltd (ASX: VUL)

The Vulcan Energy share price is up 13% to $5.38. This follows news that its Phase One Lionheart Project has officially been recognised as a Strategic Project under the European Commission's Critical Raw Materials Act (CRMA). The CRMA aims to secure Europe's supply of critical materials like lithium, which are essential for electric vehicle batteries and energy storage systems. Vulcan CEO, Cris Moreno, said: "Achieving Strategic Project status from the European Commission validates the importance of our integrated lithium and renewable energy project to European industry, and builds momentum for the delivery of Europe's first fully domestic and sustainable lithium value chain."

Wildcat Resources Ltd (ASX: WC8)

The Wildcat Resources share price is up 6% to 18 cents. Investors have been buying the lithium explorer's shares following the release of a drilling update from its Tabba Tabba Lithium Project in Western Australia. Wildcat Geology Manager Torrin Rowe said "Exploration is a part of Wildcat's DNA, resulting in the successful discovery of the flagship Tabba Tabba lithium deposit. While progressing the newly defined resource through a PFS, the team continues to advance targets with exploration drilling planned in the Pilbara, WA as well as at Mt Adrah, NSW."